Convert relative paths on opendir/open

[atoomic]

When mocking a directory and a file in the same directory we can then see . and ..
but unfortunately we have no way to mock them and they should be also provided/mocked for free for us by the directory / file

use Test::MockFile qw/strict/; 

my $d = Test::MockFile->dir("/there"); 
my $f = Test::MockFile->file("/there/xyz" => q[...]); 

opendir( my $dh, "/there") or return;
foreach my $f ( readdir($dh) ) { 
      say $f
} 

output

.
..
xyz

use Test::MockFile qw/strict/; 

my $d = Test::MockFile->dir("/there"); 
my $f = Test::MockFile->file("/there/xyz" => q[...]); 

opendir( my $dh, "/there") or return;
foreach my $f ( readdir($dh) ) { 
      -e "/there/$f"
} 

output

$>perl foo.pl 
Use of stat to access unmocked file or directory '/there/.' in strict mode at foo.pl line 8 at /usr/local/cpanel/3rdparty/perl/532/lib/perl5/cpanel_lib/Test/MockFile.pm line 238.
	Test::MockFile::_strict_mode_violation("stat", ARRAY(0xd4a360)) called at /usr/local/cpanel/3rdparty/perl/532/lib/perl5/cpanel_lib/Test/MockFile.pm line 1150
	Test::MockFile::_real_file_access_hook("stat", ARRAY(0xd4a360)) called at /usr/local/cpanel/3rdparty/perl/532/lib/perl5/cpanel_lib/Test/MockFile.pm line 612
	Test::MockFile::_mock_stat("stat", "/there/.") called at /usr/local/cpanel/3rdparty/perl/532/lib/perl5/cpanel_lib/x86_64-linux-64int/Overload/FileCheck.pm line 295
	Overload::FileCheck::_check_from_stat("e", "/there/.", CODE(0xc2a408)) called at /usr/local/cpanel/3rdparty/perl/532/lib/perl5/cpanel_lib/x86_64-linux-64int/Overload/FileCheck.pm line 265
	Overload::FileCheck::__ANON__("e", "/there/.") called at /usr/local/cpanel/3rdparty/perl/532/lib/perl5/cpanel_lib/x86_64-linux-64int/Overload/FileCheck.pm line 210
	Overload::FileCheck::__ANON__("/there/.") called at /usr/local/cpanel/3rdparty/perl/532/lib/perl5/cpanel_lib/x86_64-linux-64int/Overload/FileCheck.pm line 586
	Overload::FileCheck::_check(275, "/there/.") called at foo.pl line 8

[xsawyerx]

This can open a can of complexity.

opendir my $dh, '/there' or die $!;
foreach my $f ( readdir $dh ) {
    $f == '..' or next;
    opendir my $dh2, $f or die $!;
    foreach my $f2 ( readdir $dh2 ) {...}
}

How far should this go? What behavior do we expect?

[atoomic]

This is great example.

As I think we mock .. for free, it should exist and we should be able to open it.
If you try to open .. again then same behavior it should be mocked again and again... probably in a dynamic way.

Note that for example the following script show the same issue unmocked, you can keep looping forever on .. if you do not have the correct guards in place

#!perl

use v5.32;

sub readit {
    my $where = shift or return;

    opendir my $dh, $where or die $!;
    foreach my $f ( readdir $dh ) {
        $f == '..' or next;
        say $f;
        readit( "$where/$f" );
    }    

    return;
}

readit( '.' );

When run you would eventually get:

.
.
.
.
.
.
.
Too many open files at test.pl line 8.